The present invention relates to a semiconductor device and a technique for manufacturing the same and, more particularly, to a technique effectively applied to a semiconductor device having a heterojunction bipolar transistor (HBT) and a method of manufacturing the same.
An HBT has excellent characteristics such that, for example, it can operates with a single power source and at high efficiency as a high output device used for a high output amplifier. The HBT is therefore being actively developed and formed as a product for a wireless communication device such as a portable telephone. For example, PCT/International Publication No. WO 01/18865 by the inventors herein and the others discloses an HBT having a structure in which a protection circuit constructed by a plurality of diodes is electrically connected to an output of the HBT. Japanese Unexamined Patent Publication No. 2001-44214 discloses a structure in which all of HBT cell lines neighboring each other are disposed so as to be deviated from each other in order to make heat dissipation of a plurality of HBTs uniform. Japanese Unexamined Patent Publication No. 2000-315693 discloses a structure in which the interval between HBT cell lines in the center of a layout and that in the periphery are made different from each other to make heat dissipation of HBTs uniform. For example, an HBT amplifier for a wide-band CDMA (W-CDMA) mobile communication device is disclosed by K. Joshin et al., “Harmonic Feedback Circuit Effects on Intermodulation Products and Adjacent Channel Leakage Power in HBT Power Amplifier for 1.95 GHz Wide-Band CDMA Cellular Phones”, IEICE TRANS. ELECTRON., VOL. E82-C, No. 5, pp 725–729, 1999.